Housemate
by teawithmochi
Summary: "It's weird, noticing after two months how close they are, but he does and it's /weird/ and not entirely that bad when he thinks about it." In which suddenly living with someone is serious and not-so-serious business, and someone has to ask the heavy questions. SaiGen pre-slash, ridiculously wordy introspective fluff.


Housemate

A/N: So, uh, hi. It's been a while, hasn't it? Here's something I spent the last few days hashing out (because One Punch Man is amazing and hilarious and everything in between), and I'm not sure if I'll write anything else for a long time, but here's something.

For my friends who are still waiting patiently for the next installment of Do As You Like, I'm terribly sorry about the long delay. I'm working on it, and I've scrapped maybe fifteen thousand words already because nothing quite feels right, but rest assured I'm not giving up on it. Hopefully it won't take a year to get it done, but life is a crap game and I have more important things (sorry) to do. Like hashing out which college courses I'm going to take and wondering if I'll even survive them. But don't worry! Maybe this fic will have revived my writing spirit. Maybe.

For anyone wondering, the cover comes from a set of images that I can't remember the source of. I didn't draw any of it, but it's the inspiration for much of this story.

人( _ _ *) That said, here's some of my soul in the form of cyborg/hero fluff.

.

It's been a long day of killing monsters and rushing off to super sales, but despite that Saitama's as energetic as he usually is—that is to say, hardly enthusiastic but still more than the average person should have at this time of day. He hums a little tune that he doesn't recall the source of (it might be the theme song to a children's show, or the latest commercial jingle) and, as he's done for the past three years since he moved into his tiny apartment, pulls off his red rubber boots with practiced ease and places them off to the side of his doorway. His little disciple (though _little_ may be stretching it, considering how the kid's already nineteen) isn't present, won't be until after Saitama's done with cooking dinner with the half-priced ingredients he bought earlier, and until then the bald hero idles himself with removing his uniform (?) slash costume (?) slash work attire (?).

He ghosts into the bathroom just a step to his right, yanking off his gloves and cape before haphazardly throwing them off to one corner. He'll deal with them later, he thinks to himself (has been thinking to himself for the last two months) and ignores the voice in the back of his head that tells him that Genos will probably have them ironed and hung up in the closet, ready for tomorrow's next bout of hero-ing. It isn't his business what the young cyborg does out of his own free will, but the twenty-five-year-old in him wars with his lazy side, telling him not to let a kid do what he's been able to do by himself for so long.

And it really has been so long, but Saitama won't reminisce, won't call back those long-forgotten memories of being weak and sore and alone in this tiny apartment where he can't stretch his legs for fear of breaking the window—of finally becoming stagnant and listless in his everyday monster massacres. It's a big shift, this new life of his, but not a bad one, and he finds that he likes focusing on this routine where everything fits like clockwork and he never has to worry about things he's forgotten already.

Stripped down to his underwear, the man stretches to removes the kinks in his muscles before entering the living-cum-bedroom where he locates their shared closet to grab a jacket and a pair of sweatpants. Peering into the wardrobe (and entertaining the thought of leaping into it), Saitama grabs the first articles of clothing that he sees, throwing them on without a care.

It takes a moment for him to realize that they're a bit large on his averagely sized body.

 _Curse teenagers and their ability to grow… No, wait, he's a cyborg—he can't grow anymore. Then does that make me taller or shorter than him? In any case, let's get out of these clothes first…_ Being mindful of the cyborg's fastidious nature (he's the most hardworking person Saitama's ever seen move around a household), Saitama carefully refolds the blue hoodie and gray sweatpants. After a beat of silence, he realizes that he doesn't remember where he grabbed them from, then winces as it's his job to sort out whose clothes are whose, but he's been lazy and as a result their belongings are scattered and intermixed, the only difference that he can tell being the scent of peppermint, green tea, and motor oil on Genos' clothes.

It's weird, noticing after two months how close they are, but he does and it's _weird_ and not entirely that bad when he thinks about it. He'll sort things out after dinner, he decides, before Genos speaks up about it and makes him feel guilty for not doing his job (though it's likely that the younger male already knows). Quickly donning his own clothes after a self-conscious sniff to double check, he enters the kitchen where he's left his spoils of the day.

Cooking dinner, as usual, is a simple affair. Saitama's been living alone for so long now that even _his_ cooking skills are pretty good, and as such he's entirely at ease with chopping up the vegetables and stirring soup and doing general cooking actions—like burning his tongue on the tasting dish and almost chopping his finger off (which, now that he thinks about it, is only _almost_ because of his inhuman strength). He's not a clumsy person by nature, but the thought hits him that he's cooking for _two_ and not _one_ and suddenly he's moving almost like he's drunk and on two noodles for legs.

(Or maybe it's because he's cooking all of Genos' favorites without even realizing, and how did he not, when he hates tomatoes and yet bought them only a few hours ago, and—what's going on with him? Is this normal?)

(No, no it isn't, but Saitama's never been the most normal, and somehow it feels like this is _right_ , this oddness that isn't odd at all.)

He's just set the pot of rice down onto their rickety dinner table when he hears the door click almost imperceptibly. Saitama's always had good hearing—even before his three years of training—but time has only enhanced it, and he smiles because Genos is always careful around him, mindful of his moods and tastes and habits.

"Welcome home!" he calls out almost without realizing ( _almost_ , because he knows he's doing it, but also almost because it still catches him by surprise since he's been alone for so long and this is weird and not weird—), waving nonchalantly in his housemate's direction. Barely on the doorstep, Genos' dark-sclera'd eyes widen, and Saitama's smile widens just a bit at the younger hero's pleasantly surprised expression. The cyborg halts his every movement for some reason, too shocked to say anything as his face freezes, and it takes the man a second to place the cause before he himself stutters to a stop.

"I-I'm home, Sensei." And then everything's alright again, the moment passes by as if it never happened—but they'll both remember it and the next time it occurs it'll feel entirely too natural. But right now they're both a bit awkward and a few sizes too small for their hearts (at least, that's how it feels for Saitama) and Genos allows a tiny, unsure smile to come to rest upon his taciturn face.

Saitama's chest squeezes and he turns back to the food upon the tiny wooden table, sits cross-legged as the other heaves himself over to the seat opposite. Genos has a wire poking out of his elbow, his stance a bit too tired for his usual seiza, and idly Saitama wonders if the monster that did this to his disciple is still alive or if Genos himself needs some rest after what was probably a hard battle.

(The man's hungry, starving actually, but he's willing to postpone this meal until Genos's shoulders aren't shaking with exhaustion, don't look like they belong to an all too young Atlas, and—

Huh? Since when was he willing to give up his precious food? What's _going on?_ )

"Here, let me help," Saitama volunteers with a hint of exasperation as he sees the cyborg attempt to fix one of his fingers surreptitiously under the table. "It's a bit difficult to fix that without a screwdriver, right?" The joints are out of place and more than likely confusing the kid's nervous system (things like this, he knows even without any medical knowledge, are tricky), so he sets aside his empty (untouched) bowl, moves over to the left so that he's beside the young man instead of across from him.

This isn't the first time Genos has come home injured (nor will it be the last, as Genos always seems to be obliviously unguarded until the first strike lands) but it's the first time Saitama wants to help, decides that he _can_ help. Two months of living with a boy that's more machine than man, and he already knows the basics of android care without having to do a thing. (And if he's been stealing glances at the cyborg's robotic design on and off for a while now, then no one has to know.) At this distance, he can feel the humming of the other's inner core, basks in the heat radiating from his young friend.

"Thank you, Sensei, but it's not necessary. I can do this by myself." Stoic and resilient by nature, Genos declines his help. Or maybe it's because he doesn't want to show any weakness to his teacher. Unimpressed (Saitama knows more than anyone else that putting on airs like this won't make anyone stronger), the caped hero flicks his housemate's forehead.

His voice is cajoling, and almost a bit too light, but anyone can hear the warning in his tone—best of all Genos who knows him more than anyone in this city (or, perhaps, anyone in general). "You don't have to look strong in front of me," he offers, still smiling his usual smile. Deftly picking out the shards of monster bone in between finger joints, Saitama pops the segments back into place before twisting the minuscule screws back into place with a delicate pinch of the fingers and twist of his wrist.

Abashed, Genos' expression slips further into self-deprecation (goodness, for an S-class hero, he's certainly lacking in confidence, isn't he?), and he looks away. "…Thank you, Sensei. You should eat dinner without me. I have something to do." With a hand on his head (the same spot that Saitama just flicked him) he stands up.

Saitama's grasp on his hand (it's warm and not in a human way, has no pulse, but he doesn't care because it's _warm_ and _there_ and he can _hold_ it) pulls the cyborg back into orbit, yanks him into place before he can run away and retreat to wherever he goes when he's feeling like he's useless. It's a feeling Saitama can relate to all too well, which is why he only smiles wider and pats Genos' (doubtlessly confused) head like it's nothing. "You're perfectly welcome, dude. And I will, if you don't mind keeping an old guy like me company."

Saitama knows that his expression is too deviously expectant, too manipulating for it to look innocent in any way, but if Genos notices he doesn't say. All Genos does is give him a helpless smile and he stays put.

"Sensei is not old."

Right. That's the end of that.

As Saitama shoves food into his mouth, Genos begins eating, taking in small, efficient bites of food that would have made Saitama uncomfortable once upon a time—or at the very least fascinated—but all he can feel now is a curiously strong fondness for this student who's forced his way into his teacher's home, who's forced his way into Saitama's habits and tastes and moods. It's still fascinating on some level (watching a hunk of metal eat is always interesting), but now all too mundane, and yet he can't look away.

"Sensei."

He gulps down some soup. "Yes?"

"Is there something on my face?"

Saitama's about to say _no, what are you talking about_ before his mind catches up with his actions, and he twitches slightly (it's a bit creepy to be so fixated on another person like this, isn't it?) but he can't say no and he can't say yes. What's the saying—

Damned if you do, damned if you don't. Fortunately even neat cyborgs like his student can make a mess when eating ( _he's only nineteen, what were_ _ **you**_ _doing when you were nineteen, huh, Mr. Hero?_ ), and it's but a moment before he's leaning over with a blank expression on his face, picking a couple of rice grains from Genos' cheek. "Yes," he says simply, all too grateful for these tiny pieces of rice that have given him a way out.

There's an odd grinding noise in the room, something between a groan and mewl of mortification crossed with a bit of failing machinery, and Genos' face reddens as if there's really blood underneath that synthetic skin. Strangely enough, Saitama never gets enough of Genos' embarrassed moments. Kids are cute.

("I'm not a kid anymore, Sensei."

"Well, you're younger than me by that much, and you're my disciple. I can call you with that amount of familiarity, can't I?")

Genos is exceedingly careful for the rest of the meal.

An hour later, Saitama sits in his bathtub, sinking deep into the water so that only the top of his ears and his knees are exposed. It's a tiny thing—cheap, too, unable to hold heat for longer than ten minutes—but Saitama doesn't mind, actually likes it. It's one of the only places in the house where he can be alone, because Genos doesn't need to bathe (he does, however, brush his teeth almost religiously), and for a guy who's adjusting to a shared living space so (too) well, Saitama's been by himself for so long that being alone at times is good. Fine. Comfortable in the way a well-worn scratchy hoodie is due to familiarity.

For a moment he forgets that he's actually living with someone, revels in the solidarity, but then he hears the slightest vibrations of the radio outside (something he bought recently as a gift for the cyborg of justice that always hangs onto his every whistle, hum, bar of music) and jerks awake, splashing water everywhere. Come to think, it's as if the kid hadn't heard of music before, or maybe had forgotten it, but Saitama won't ask about what happened during those four years before now, and Genos is reticent enough not to divulge. Instead, the older man makes it his duty to care for this awkward kid who's too stern with himself, and, well—it's nice seeing him smile every once in a while for absolutely no (every) reason.

Maybe it's the sound of the hesitant singing from outside, or the water becoming lukewarm, but Saitama begins shivering with a feeling akin to anticipation. Genos is whispering, probably all too aware of his teacher bathing just fifteen (or so, he doesn't really know) paces to the left of where he's sitting, but Saitama's always had the greatest hearing, and he counts it as a miniature blessing at this moment because this is a precious scene he's not supposed to hear, forbidden in some way that entices him greatly.

…Gods, he really is a creep, isn't he?

From then on, every sound jerks him hyperaware, and just to prevent his poor old bathtub from breaking under sheer duress (and to keep old lady Fujiwara from harping about installing new appliances) he spares a moment to lament his peace and silence before calmly sliding out into the cold air of an evening bathroom with no air conditioning. Saitama sneezes, wonders if he'll catch a cold when he hasn't had one in two years, before drying off with a quick series of steps that force the droplets from his skin. His old pajamas are soft against his skin, with less of an edge and missing the frayed threads that used to plague the hems. It's probably Genos' influence.

He smiles.

Outside Genos has the futons set out, is sitting against the wall listening to his music in silence as if he wasn't singing just a moment ago. Saitama normally watches the television at this time (he blames King for his addiction to Yakimomonga, but it's also his fault for being so amused by a farting potato-hero) but it feels wrong to disturb this peaceful air, so he heads for the bookshelf by the window-cum-balcony and grabs a book at random.

And of _course_ it's one of Genos', floppy at the edges and dog-eared, with countless little tears at the seam where the younger hero seems to have been unable to control his strength. Saitama takes a glance at the cover, then at the synopsis on the back. Typical and so penultimately _shounen_ , it comes as no surprise to the older man who knows that Genos loves justice and friendship and stubborn strength as much as—or more than—the next teenager. He casts a sly look in said teenager's direction, carries the worn thing back to his futon. Flips it open.

There are photographs inside.

Saitama carefully shuts the book, returns it to the shelf, and grabs an old edition of Young Jump instead. He feels curious eyes on the back of his head and grins a bit sheepishly, apologetically, feeling as if he should have asked, should have checked to make sure… but Genos was too late to see which book he had chosen, and Saitama wants to keep it that way.

No pushing, no questions. That's how it's been for the past two months. Of course, Genos always has to surprise him (yet again. He'll never stop surprising him.).

The moon is weak tonight, the thinnest sliver of light against a backdrop of stars too dim to be seen in the smog-filled air of a former factory plant like Z-City. It casts a faint halo on their futons, paints an arc of stark white against their faces, and it might be because of the book that's still on his mind or the warm body of a not-automaton beside him, but he doesn't want to sleep just yet—which is a stupid thought, since there's a free raffle event going on early tomorrow morning that Saitama just _has_ to get to, or he'll lament the loss forever (or until the next one comes along). Genos seems to feel his unease, yet stays his silence for fear of breaking the delicate tension between them.

Finally, someone's curiosity cracks and it's not Genos'.

"Is something wrong, Sensei?" Genos asks, golden eyes piercing and luminescent in the darkness. He doesn't sit up—this isn't the type of conversation where they need to, not yet—but the hesitance is there, and Saitama hurries to allay it.

He turns over on his side with one arm propping his head up. As per usual his face is bland in its friendliness, and Saitama replies, "Nothing's wrong. Just having a rough time falling asleep is all," but it's a shoddy poker face at best and he knows it. It's likely that the cyborg does as well, judging by the serious frown on his face and the frustrated look in his eyes.

He's probably thinking about something—his strength maybe—and _when will he ever learn_ that Saitama isn't natural, that he _does_ have strength and all he needs is life experience and a lead on that mysterious cyborg that killed his family, that Genos doesn't _need_ to be so attentive to Saitama's every minor whim, to be here, so closely tied to Saitama's lifestyle now that it's weird and _not_ weird and _he doesn't want to be alone again?!_

The twenty-five-year-old realizes that he's breathing just a hair (hah) too shallowly, the slightest bit over the line between even and wild, and shudders a bit trying to calm himself. Genos' worry is almost palpable in the air, and oh yes, that's right, there's a hole in his mattress now. Wonderful.

There's a sigh in the room, taking up the space between the two, and for a moment Saitama's not sure who uttered it. Maybe it was Genos or maybe it was him, but that doesn't matter because now Genos is leaning over him and frowning and there's that seiza that always makes him look so serious and—

"Sensei?"

Saitama chokes a bit on his spit.

"Yeah?"

"What are you thinking about?"

 _You. And me. And more of just living together with you. And why is it so natural and unnatural and confusing and_ _ **why**_ _am I still letting you stay here?_

"Being a hero is nice, isn't it?" he asks instead, side-stepping the question with a cowardice he had forgotten he possessed. Then again, he's only ever weak in emotions these days so it's easy to forget.

Genos seems confused by the sudden question, knows the avoidance when he hears it, but lets it pass because he's careful and mindful and only wants to help. He answers seriously, however, and that might be what sets the older man on edge.

"Is this about my progress? I'm doing my best to get into the top five as you've instructed," he relays with a contemplative look on his face, "and I'm recording all of your teachings into my notebook."

Metaphysically, Saitama dies a bit on the inside. "That's… nice."

Oh, no. Genos is frowning now. "Am I going too slow for you?" the cyborg questions, and it sounds almost desperate at this time of the night (morning). "I'll work harder tomorrow to defeat more monsters, but there are only so many around and—"

"Genos," Saitama interrupts, and it suddenly dawns on him that this is probably the first time he's called the teenager by his own name to his face. It generates a full body shudder in the teenager's metal body, and Saitama wants to slam his head into a wall because… Because what, exactly? Because he's annoying? Because he's speaking too fast? Because it's more than ten words?

…Because this kid is actually quite endea—?

"You're doing fine," Saitama tacks on, because just saying Genos' name seems a bit weird by itself, and because he doesn't want to finish that thought. That also sounds stilted, though, so he adds, "That's not the issue here."

"Then what is?"

And isn't that the real question here? Saitama stalls a bit. Suddenly the ceiling looks all too interesting with its cracks and conspicuously new areas where monsters deemed it fit to crash into his home via gravity. It's a view that he's usually too tired of staring at in fitful moments during the witching hour, but now he can't take his eyes away. Won't, when the only other alternative is Genos' face, and it isn't like he has anything against the kid but those eyes make him feel too open, too much like he's bursting at the seams.

Eventually Genos tires of the silence (which usually never occurs, but this is a special occasion apparently), and it's only Saitama's inhuman reflexes that prevent him from punching that handsome face into bits of scrap metal when the cyborg leans over his face. The surprise shows, though, and Genos is quick to back off, an apologetic look on his ever-shifting face.

(He's only ever so expressive when they're alone together, and Saitama's not quite sure what to think about this fact.)

"You seem troubled." This statement seems to trouble Genos himself, pulls at his brows and rearranges his face into a pensive glare directed at the floor. It makes Saitama's chest do a sort of quiver-flop-tremble, the same kind that helplessly watching a disaster elicits, and he has to swallow the lump in his throat before he can reply with something he hasn't planned out. What to say comes after being able to say, and before that is remembering how to breathe.

So he breathes, swallows, thinks. Rethinks. "What are you going to do once you defeat this mysterious cyborg of yours?"

It's not the right question to ask, but usually there are no right questions—just questions that do and don't need to be asked—and for this night Saitama decides to ask it because if he doesn't do it now then he never will. Genos looks like he's been hit by a bullet train (or if not a train, then something equally as heavy and surprising), exhales a bit too quickly to sound casual, looks up. Looks down. Closes his eyes.

"Did you find my photo album?" Despite his asking, it's clear that Genos knows, and Saitama doesn't need to say yes or no because he's already pushing forward with another response. "No, that doesn't matter. To be honest…? I haven't planned that far yet.

"It's weird, isn't it? I've spent so much time devoted to becoming stronger, to track him down and get some answers… I'm almost entirely made of metal right now. I used to stay up all night wondering what I would do once I got my hands on him, but I don't know what I'll do after that. In the first place I wonder if I'll even find him at all."

He's perturbed by this last thought, letting a stain of despair enter into his eyes, and Saitama moves without thinking, sits up entirely (because now he has to, he can't just lie down for this) so that he can gently ( _gently, gently, I can't hurt him when he's like this_ ) pat Genos' head. Saitama isn't sure why he does it. He doesn't even like it that much because Genos' hair, while feeling entirely too real, pokes into his skin and it's all really awkward, but—it _feels_ right. Because Genos is young and confused and Saitama remembers what it was like to be like that. He might not have had his family killed out of nowhere, never had to deal with making his body into an automized weapon, but he does know what getting used to his own skin feels like, knows that he would have given up anything for some semblance of comfort in his most twisted moments.

"You will. I have faith in you," he says instead of anything resembling an offering of help. This is a revenge plot, a singular attempt, a personal issue that needs to be resolved by itself, and Saitama won't ruin it. Genos would take it if he offered, but he'd be reluctant so the caped hero won't push it. Instead he gives the kid a different push of his own, gives him faith that he can, and that's about as much as the man can offer right now.

Genos recognizes it and takes it as it is. "Thank you, Sensei," he says with a slightly vulnerable smile, and it makes Saitama's heart stop because—

 _This kid, seriously! This isn't good for my heart!_

"Genos."

"Yes?"

"After all of this is done, stay a hero with me."

"…Okay."

.

.

.

That morning, Saitama wonders why they have a second futon if Genos doesn't even sleep in it to begin with.

(Maybe that was what bothered him so much in the first place.)


End file.
